Raman spectroelectrochemical studies and crystal structure of a binuclear copper(I) complex with a bridging diimine ligand


Autoria(s): Gordon, Keith; AlObaidi, A.H.R.; Jayaweera, P.M.; McGarvey, John; Malone, John; Bell, Steven
Data(s)

1996

Resumo

Raman spectroelectrochemical and X-ray crystallographic studies have been made for the binuclear copper(I) complex, [(Ph(3)P)(2)Cu(dpq)Cu(PPh(3))(2)][BF4](2), where dpq is the bridging ligand 2,3-di(2-pyridyl)quinoxaline. The X-ray data show that the pyridine rings are twisted out of plane with respect to the quinoxaline ring which is itself non-planar. The UV/VIS spectra of the metal-to-ligand charge-transfer excited state and those of the electrochemically reduced complex are similar. The resonance-Raman spectrum of the latter species exhibits little change in the frequency of the pyridinylquinoxaline inter-ring C-C bond stretching mode, compared to the ground electronic state. This suggests minimum change in the inter-ring C-C bond order in the electrochemically or charge-transfer generated radical anion. Semiempirical molecular-orbital calculations on both the neutral dpq and radical anion show two near-degenerate lowest unoccupied orbitals in the neutral species. One is strongly bonding across the inter-ring C-C bond while the other is almost nun-bonding. The Raman data suggest that it is this latter orbital which is populated in the transient and electrochemical experiments.

Identificador

http://pure.qub.ac.uk/portal/en/publications/raman-spectroelectrochemical-studies-and-crystal-structure-of-a-binuclear-copperi-complex-with-a-bridging-diimine-ligand(98878a32-f85f-4444-bd20-b6649e0433be).html

Idioma(s)

eng

Direitos

info:eu-repo/semantics/restrictedAccess

Fonte

Gordon , K , AlObaidi , A H R , Jayaweera , P M , McGarvey , J , Malone , J & Bell , S 1996 , ' Raman spectroelectrochemical studies and crystal structure of a binuclear copper(I) complex with a bridging diimine ligand ' JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS , vol 1 , pp. 1591-1596 .

Tipo

article